SystemIt jet-spiral oil on top of the surface of a bed filter inside a vacuum housing -the oil's surface areas become larger while falling down slowly inside the vacuum housing -the vacuum housing is kept at -0.06Mpa with a vacuum pump -it removes the moisture away from the surface of oil when the dry air blows on oil in this conditions -the moist air comes out from the outlet of the vacuum pump -The same conditions as the washed clothes become dry.